Means for preventing the backrolling of autos



Nov. 8, 1938. c JAMESON 2,135,896

MEANS FOR PREVENTING THE BACK-ROLLING OF AUTOS I Filed April 11, 1952 2 Sheets-Sheet 1 AUT BRAKE ROD INVENTOR.

Nov. 8, 1938.

c. M. JAMESON MEANS FOR PREVENTING THE BACK-ROLLING OF AUTOS 2 Sheets-Sheet 2 Filed April 11, 1932 INVENTOR.

Patented Nov. 8, 1938 MEANS FOR PREVENTING THE BACK- ROLLING OF AUTOS Charles M. .lameson, Pasadena, Calif., assignor to Automotive Devices, Inc., a corporation of California Application April 11, 1932, Serial No. 604,401

Claims. (Gl. 192-4) This invention relates to improvements in drawings, and specification, and then more parmechanism for stopping an automobile or similar ticularly pointed out in the appended claims.

vehicle when it is desired to cease movement of In the drawings, taken on line l| of Fig. 3 the machine for various causes. wherein similar reference characters designate 5 One of the objects of this invention is to prosimilar parts throughout the respective views, 5 vide a simple, efiicient and inexpensive device Figure 1 is a sectional elevation of the parts of whereby, independently of the will of the opermy invention, ator the car may be quickly stopped, especially Figure 2 is a top plan view of certain parts of when it is necessary to prevent the back-rolling my invention,

of the machine on a grade. Figure 3 is an end elevation of my invention, 10

It is Well known that when an automobile shown mounted upon a frame, and taken on line reaches the top of a sharp grade or hill, in plac- 33 of Fig. 1,

ing the gear shift lever in neutral before the Figure 4 is a side elevation of the carrier for brakes are applied, or when moving the gear the dogs that operate the ratchet wheel, formshift lever out of neutral to place it in first speed ing part of my invention, 15 position, after the brakes have been released the Fig. 5 is a diagrammatic view of the parts of my car has a tendency under the force of gravity to invention shown in their positions after operation roll backwardly down the hill, making it difficult of my automatic means for applying the brake. to start the machine on its forward movement. Fig. 6 is a similar diagrammatic view of the In a copending patent application, filed by me parts of Fig. 5 showing the parts in their normal 20 on the first day of February. 1932, bearing Serial positions before operation of my automatic means Number 590,169, I have disclosed certain details for applying the brake upon back-rolling.

of construction that have to do with preventing Fig. 7 is a diagrammatic view of gear positions the back-rolling of the machine due to a releasshowing the transmission in forward gear and the ing of brakes, Where the stopping means is indedevice in operative condition. 25 pendent of the brake mechanism. In the pres- Fig. 8 is a diagrammatic view of gear positions ent application I make use of the same instrushowing the transmission in reverse gear with mentalities as before but use in conjunction therethe device in inoperative condition. with certain parts by which the braking mech- Fig. 9 is a diagrammatic view of gear positions anism will be operated at the same time as the showing the transmission in neutral gear fol- 30 means controlled independently of the braking lowingreverse, and the device in inoperative conmechanism and which also stops the car. dition.

A further object of the present invention is to In the drawings, wherein similar reference provide means for stopping an automobile to precharacters designate similar parts thruout the 5 vent it rolling down a hill which is controlled respective views, and wherein the parts are merely automatically as the gear shift lever and clutch illustrative of my invention the invention disof an automobile is being operated. Should anyclosed performs the function of stopping an autothing happen to the braking mechanism of the mobile from rolling backwards on a grade. l0 machine whereby it becomes impaired or out of designates y Suitable a e on the car, and H order, the car .will still be stopped automatically is a ratchet wheel whose an e 2 is centered in 40 so as not to roll backwardly on the hm or grade relationship to a retaining ring it. It is preferred A fi al purpose of this invention is to provide to form thefiange [2 upon the ratchet wheel, and

a dual control of the stopping mechanism for an to fit this flange into the rabbeted portion M automobile whereby the usual brakes are of the retainer ring I3. I form a series of cir- 4 cumferentially spaced apart arcuate slots H in i g f g i fi fig 2 w s the retainer ring [3 as well as in the flange l2 r0 mg ereo accl en W 1 S Owmg Vac of the ratchet wheel, and I cause a series of screw {011mg at the Will of the operator, as when revers' threaded bolts IE to project thru these arcuate ing the car on a grade, and whereby mea slots ll, so that their heads l8 bear against the independent of the brakes are operated for the retainer ring 3 and so that nuts 5 may be 50 Purpose Of also Stopplng the to event backscrewed home upon the screw threaded portions,

rolling thereof. to clamp the retainer ring and the flange of the With the above and other objects in view, my ratchet wheel together loosely. invention consists in the combination, arrange- It will be seen that the hub 2| of a spider or ment, and details of construction disclosed in the dog carrier 19 is fixed upon the shaft B by means 55 of the key 20 and extends rotatedly into the ratchet wheel II, and carries the pivot pins 22 upon which the series of dogs A are eccentrically mounted for movement. Each dog has a stout claw of proper proportions 5|, designed to come into engagement with the teeth of the ratchet wheel under the proper conditions. The outer terminals of the dogs are respectively formed with beveled edges 23. 24 designates a shifter which consists of a disk like body having a series of right-angularly projecting arms 25, 26, and 21 7 formed integrally thereupon and designed to engage with the dogs A, in a manner about 'to be explained. The outer ends of the arms 25, 26, and 21 are also formed beveled at 28 for engagement with the beveled edges of the terminals of the respective dogs. Upon advancing the shifter 24 through a force applied against it by shiftable gear 34, the bevel 28 of the outer end of the shifter arms 25, 26 and 21 will engage the counter-bevelled edges 23 of dogs A thus raising the engaging ends 5| of the dogs out of engagement with teeth of ratchet wheel The shaft B is formed with a series of longitudinally extending spline ribs 35, designed to fit the correspondingly shaped recesses 45 of the bore of the shifter 24 as shown in Figure 4. It will be observed that the shifter is provided with a series of sockets 29 of a diameter larger than the diameters of a series of screw threaded bolts, 39 whose heads are designated 3|. The two standard gears 32, and 33 of the usual transmission train of an automobile are shown, operating in conjunction with the shiftable gear 34 which is splined upon the ribs 35 of the shaft B so as to slide thereon and rotate therewith. 36 designates the usual gear shift lever the handle of which is designated 31. The usual gear box 38 is also disclosed and the gear case 39. This gear case is formed with the elongated slot 40 in which is slidably mounted the crank arm 44 which is operatively attached to the flange I2 of the ratchet wheel H, the movement of the ratchet wheel communicating power and action to the crank arm 44.

The crank arm 44 carries a crank pin 42 upon which is pivoted the connecting rod rocker link 4| formed at its inner end with a fork 46 through which the crank pin 42 passes. A sleeve 68 is carried by the rocker link 4|, and into its other end the right handed threads of a turnbuckle 10 are received, the other end of this turnbuckle having left handed threads which also screw home into the sleeve 69. The latter is pivotally attached to one arm 14 of a bell-crank lever, the other and right angular arm of which, 13, reacts against the shoulder or nut 12 fixedly mounted upon the usual rod II that operates the brake mechanism of an automobile. A brace arm 15 connects the arms 13, and 14 of the bell-crank lever for reinforcing purposes, this lever being pivoted upon any desirable support 16. A spring 11 is operatively coiled around the rod 1| being associated'in connection with a stand 18 as shown in Figure 2. As illustrated in Fig. 2, an upward movement of rod 1| applies the brakes. The shaft B is formed with two or more nicks 52 upon its face into any of which the ratchet ball 53 may be pressed by a spring 54 suitably housed in the shifter 24, the spring being confined in the latter member by any means such asthe screw plug 55. I

In operation the ratchet wheel and associated parts function in the identically same manner as described in my co-pending application filed on first day of February, 1932, and bearing Serial Number 590,169. However, due to the formation of the arcuate shaped recesses or slots H, the ratchet wheel is allowed a slight movement determined by the distance that the securing bolts l5 allow. Normally, when the automobile is in action in any of its forward speeds, the centrifugal force set up would disengage the dogs A from the teeth of the ratchet wheel, as the forward movement of the car prevents the hazard of backrolling thereof. But when the speed of the machine slackens materially to a slow run, the dogs engage the ratchet wheel, and if the brakes are off, and the car tries to roll back, the back movement will momentarily carry the ratchet wheel along with it, and the ratchet wheel rotates the distance of the length of the arcuate slots l1, and no more. The wheel N then comes to a stop. This occuring the crank arm 44 moves with the -ratchet wheel a sufficient distance to move the rocker link 4| and turnbuckle connections in the right direction, to cause the arm 13 of this lever to actuate the brake mechanism by means of the brake rod H, from positions as shown in Fig. 6 into those shown in Fig. 5, and the dogs which have thus caused the ratchet wheel to move will now remain at rest against the teeth of the ratchet wheel, since the latter is at rest so the car is held by virtue of the operation of the brake mechanism as Well as by means of the interengagement of the dogs with the teeth of the ratchet wheel. When the shifter arms move to engage the dogs to retract the latter, the beveled ends 28 of these shifter arms engage the beveled ends 23 of the dogs so by allowing the arms to ride over the beveled ends of the dogs these ends of these dogs are depressed and the claws thereof are raised out of engagement with the ratchet wheel. When new the gear shift lever 36 is operated to place the gears in low speed position, the parts will be as shown in the diagram illustrated in Figures 4 and 7, and the shiftable gear 34 has moved in the position shown there being play between the shifter 24 and this gear as the screw rods 30 are extended during this idle interval, Without disturbing the position of the other parts, so the dogs still hold upon the stationary ratchet Wheel and the brake mechanism is still in operation, being so indicated in Figure 5.

When, upon authorizing rearward movement of the automobile, the shiftable gear is moved into reverse position as shown in Figure 8, it comes into contact with the shifter 24 in its position of Figure '7 and it bodily forces this shifter towards the left which causes the arms thereof and especially the beveled edges 28 of these arms to ride against the beveled edges 23 of the dogs, and thereupon the terminals of the dogs are tipped and the claws thereof disengaged from the teeth of the ratchet wheel, and now the dogs no longer hold the car against back rolling, and as this takes place the crank arm 44 is restored to normal position in its slot 40, so the brake mechanism is released. The car may now be reversed without interference either from the dogs or from the usual braking mechanism which have been automatically operated up to this time. If, whilst reversing, the operator wants to roll back hill faster and not depend upon his slowness in reversing, he may shift the shiftable gear 34 back from the shifter 24 into neutral position as shown in Figure 9 and this action will not disturb the released condition of the dogs, as the shifter will not move in unison with the reverse movement of the gear. If, however, the operator shifts gears into forward low gear position, as shown in Fig. 7, the gear 34 moves to the right and through bolts 30 pulls shifter 24 away from the dogs permitting the dogs to again engage the ratchet when the car comes to a slow speed. Thus, the ratchet and dog mechanism is in condition for preventing unauthorized rearward movement of the vehicle only when the transmission is in a forward speed or in neutral following a forward speed. When the transmission is in reverse or in neutral following reverse gear, the mechanism is not in condition to prevent back-rolling of the car. In this manner it is seen that complete control is given to the operator of the car of the mechanism for stopping the car from back-rolling.

I do not mean to limit myself to the exact details of construction herein set forth but cover all variations falling within the purview of the appended claims.

What I desire to claim and secure by Letters Patent is:-

1. In a device as described, the combination of an auto brake mechanism, a ratchet wheel capable of undergoing a limited rotation, dogs associated with said ratchet wheel and designed to engage the same, a gear shift lever, a rotary member actuated when the auto gear shift lever is set for forward speed or in neutral position following any forward speed and during a slight back rolling to cause the dogs to actuate the ratchet wheel in rotary movement, and means operated by the ratchet wheel as it moves for automatically applying the brake mechanism.

2. In an automobile. the combination of a brake mechanism, a transmission shaft, a ratchet wheel on said shaft having a limited rotary movement thereon, but otherwise being rigidly unrotatedly positioned, dogs engageable, during slow speed of the auto, with said ratchet wheel, a carrier for said dogs connected for rotation with the transmission shaft, designed to actuate said dogs to turn the ratchet wheel when the auto rolls back, and means controlled by said wheel for applying the brake mechanism.

3. In an automobile equipped with brakes and having a transmission and a transmission shaft, the combination of a ratchet, dogs engageable with said ratchet, a carrier for said dogs moved by said transmission shaft independent of the setting of said transmission, said dogs cooperating with said ratchet to move said ratchet upon unauthorized rearward movement of said automobile, and means in connection with said ratchetcontrolled by movement of said ratchet for applying the brakes.

4. In an automobile, the combination of brakes, a transmission shaft, means for automatically applying the brakes upon rearward movement of the automobile comprising a ratchet wheel concentric with said transmission shaft, dogs engageable with said ratchet wheel, a carrier for said dogs connected for rotation with said transmission shaft, said dogs adapted to cooperate with said ratchet wheel to move said ratchet wheel upon rearward movement of the automobile, an operative connection between said ratchet wheel and said brakes for applying the brakes when the ratchet wheel is moved, and additional means adapted upon authorizing rearward movement of the automobile to lift and hold said dogs out of engagement with said ratchet wheel.

5. In an automobile, the combination of brakes, a transmission having forward, neutral, and reverse positions, a transmission shaft, means for automatically applying the brakes upon rearward movement of the automobile comprising a ratchet, dogs engageable with said ratchet, a carrier for said dogs moved by said transmission shaft, said dogs adapted to cooperate with said ratchet to move said ratchet upon rearward movement of the automobile, an operative connection between said ratchet and said brakes for applying the brakes when the ratchet is moved, and additional means adapted to render inoperative said first means when said transmission is in reverse position or in neutral position following reverse.

CHAS. M. JAMESON. 

